Jeff Bezos is about to have $100 billion reasons to be thankful. And it's all happened so quickly! Just a few months ago, the Amazon CEO's net worth was $80 billion. In Late October, Amazon's stock surged after a strong quarterly report. That surge sent Jeff's net worth zooming above $90 billion and for the first time Jeff overtook Bill Gates to become the richest person on the planet. Well, it's only been about a month and now $90 billion feels like it's a million miles away.

As of this writing, Amazon's stock price is up nearly 3% on the day. That increase is thanks largely to the company's Black Friday success, which is still underway. Americans reportedly spent $1.5 billion online on Thanksgiving evening alone.

The stock is currently trading at $1179 per share. Bezos owns 80 million shares. That means his Amazon stake alone is worth $94 billion.

When combined with his various other assets and investments, it's not unreasonable to estimate that Jeff Bezos has a net worth of $97 billion at this moment.

In July 1999, at the peak of the dotcom bubble, Bill Gates' net worth briefly hit $100 billion. When you adjust for inflation, that's technically the same as $140 billion today. Oh and btw, as the dotcom bubble burst over the next 12 months, Gates' net worth dropped down to $40 billion.

While we're adjusting for inflation, here's a list of historical figures who had net worths larger than $100 billion and the year they pulled it off:

#17 Stephen Girard – $105 Billion

French born shipping and banking mogul Stephen Girard died with the equivalent of $105 billion in 1831. Girard didn't have any heirs so he left the bulk of his estate to charity.

#16 John of Gaunt – $110 Billion

John of Gaunt was England's King Richard II's Regent and had a net worth equal to $110 billion in today's dollars thanks to very generous land grants.

#15 Richard Fitzalan 10th Earl of Arundel – $118.6 Billion

The 10th Earl of Arundel also known as Richard Fitzalan, was a prominent English nobleman and land owner who had a net worth equivalent to $118.6 billion at the time of his death in 1376.

#14 John Jacob Astor – $121 Billion

John Jacob Astor has the honorable distinction of being the very first American multi-millionaire in history. He made his first million by trading furs from Canada to wealthy women in New York City. He used his money to acquire vast amounts of real estate and had a net worth equivalent to $121 billion when he died in 1848.

#13 William de Warenne – $147.13 Billion

William de Warenne, the first Earl of Surrey, was an English military leader and nobleman who was awarded large grants of land for his service during the battle of Hastings. That land was worth the equivalent of $146.13 billion in 1088.

Alan Rufus was the 11th century military companion of William The Conqueror. Going to war with William was a very profitable endeavor. Rufus was given 250,000 acres of land in England, which at the time was worth the equivalent to $178.65 billion.

#10 Cornelius Vanderbilt – $185 Billion

Cornelius Vanderbilt is the third richest American ever, the 10th richest person in history and CNN anchor Anderson Cooper's great-great-great-grandfather. Cornelius Vanderbilt made his first fortune in the steamboat industry but didn't see his wealth really explode until he invested in railroads at the age of 70. When he died, his estate was worth the equivalent of $185 billion.

#9 Henry Ford – $199 Billion

Ford motor company founder Henry Ford built an iconic brand which we all still know and see today. At the time of death in 1947, he had accumulated a net worth equivalent to $199 billion modern dollars.

#8 Muammar Gaddafi – $200 Billion

After his death in 2011, reports surfaced that Muammar Gaddafi was secretly the wealthiest person in the world with a net worth of $200 billion. In the months surrounding his death nearly $70 billion in cash was seized in foreign bank accounts and real estate. Muammar Gaddafi's iron fisted rule over Libya's oil fields made up the rest of his net worth.

#7 William The Conqueror – $229.5 Billion

William The Conqueror lived from 1028-1087 and was most famous for invading and subsequently seizing England in 1066. When you spend a lifetime conquering other kingdoms, you tend to acquire quite a bit of money. In Williams case, when he died he left the equivalent of $229.5 billion to his sons.

#6 Mir Osman Ali Khan – $230 billion

Mir Osman Ali Khan, also known as The Nizam of Hyderabad, was the ruler of Hyderabad until the country was invaded by neighbor India. Mir Osman Ali Khan had a personal collection of gold that was worth more than $100 million and owned over $400 million worth of jewels including the famous Jacob Diamond which is worth $95 million today. Khan used the diamond as a paperweight in his office. He supposedly owned more than 50 Rolls Royces.

#5 Nikolai Alexandrovich Romanov – $300 Billion

Nikolai Alexandrovich Romanov, also known as Tsar Nicholas II of Russia, ruled the Russian empire from 1894 to 1917 when Bolshevik revolutionists overthrew and murdered him and his family. In 1916, Tsar Nicholas II's net worth was nearly $900 million which is the inflation adjusted equivalent to $300 billion in 2012 dollars. With $300 billion makes him the fifth richest person in history and since the Russian Orthodox canonized him, he is the richest saint in human history.

#4 Andrew Carnegie – $310 Billion

Andrew Carnegie made his vast fortune when he sold his Carnegie Steel Company to JP Morgan for $480 million in 1901. That equates to a peak net worth equivalent to $310 billion in modern dollars. When he sold his company to JP Morgan, Carnegie took home $230 million worth of gold bonds and received a 5% annual coupon to top it off. The bonds sat in a bank in New Jersey which Carnegie never visited. After selling his company, Carnegie retired from business life and dedicated his time to charity. He gave away the majority of his fortune during his lifetime and his final $30 million was donated after his death. Many universities and foundations still bear his name today.

John D. Rockefeller is the richest American who ever lived. At the time of his death in 1937, Rockefeller was worth the equivalent of $340 billion in today's dollars. His company, Standard Oil, dominated American Oil production and was eventually broken up by the US Government for being a monopoly. Standard Oil was broken into smaller companies that you probably recognize today: Amoco, Chevron Conoco, and ExxonMobil. Rockefeller was the first American to ever have a net worth over $1 billion.

#2 The Rothschild Family – $350 Billion

The Rothschild family are the richest people on earth today with assets that total at least $350 billion. Their net worth is difficult to peg because their holdings are so vast, but without question they are the most powerful family in the world. Many people believe they control over $1 trillion in real estate and banking assets alone.

#1: Mansa Musa I – $400 Billion

Mansa Musa I of Mali is the richest human being in history with a personal net worth of $400 billion! Mansa Musa lived from 1280 – 1337 and ruled the Malian Empire which covered modern day Ghana, Timbuktu and Mali in West Africa. Mansa Musa's shocking wealth came from his country's vast production of more than half the world's supply of salt and gold. Musa used his wealth to build immense mosques that still stand today, nearly 700 years later. His kingdom and wealth didn't last much longer after his death. His heirs were not able to fend off civil war and invading conquerors. Just two generations later, his world record net worth was gone.